So You Think belatedly tasted success at Royal Ascot as he collected the tenth Group One of his globe-trotting career when taking the Prince of Wales's Stakes at Royal Ascot, but in an unusual postscript to the race winning trainer Aidan O'Brien was left apologising for "nearly ruining" the horse's career.

Edged out in the dying strides by Rewilding in the race 12 months ago, So You Think (4-5 favourite) made amends with a convincing victory over Carlton House (7-2), who led with over a furlong to run but had no match for the sustained challenge of the winner and went down by two and a quarter lengths.

Farhh (6-1), upon whom Frankie Dettori attempted to chart a precarious passage from the rear, endured little luck in running and finished fast enough to grab Reliable Man for third without being able to show his true colours.

So You Think, who was the first winner at Royal Ascot for 19-year-old Joseph O'Brien, the trainer's son, is now set to sign off from his racing career in Sandown's Coral-Eclipse Stakes early next month before heading into quarantine and returning to Australia to begin life as a stallion.

Aidan O'Brien has held his hands up to mistakes with other horses in the past, but with So You Think probably needed to perform no better than when second in the race last year, it was rather unconvincing to hear the trainer apologise to Australian racing fans for "mucking up the horse's career for the last year and four months".

So You Think's achievements on the racecourse have not always lived up to the blaze of publicity and high expectation in which he arrived at Ballydoyle early last year.

This, O'Brien blamed upon the way in which he had trained the horse, saying that he now wished he had listened more to So You Think's former trainer Bart Cummings.

"Bart always said he was a speed horse and I tried to train him for stamina," said O'Brien. "I over-worked him and got him wrong. I apologise to all of the Australian racing fans. We expected a big run today, we felt like we had him in a place that he was never in before with us, which is incredible.

"We went back and listened to what everybody was saying about him, listened to what Bart was saying and telling us what to do and what not to do. We listened at the end. We felt he was in a place today he's never been in before.

"Everyone was of the opinion before we got him that he was all speed but I started off on the wrong leg with him and tried to make him stay a mile and a half and did too much with him. We knew we only had a few runs left (before retiring to stud), maybe today and Sandown to get him back, so we listened to them and Joseph and the lads were confident it was going to come."

Favourite at the start of the week to be the meeting's leading trainer, O'Brien had belatedly got off the mark in the opening Jersey Stakes when 20-1 chance Ishvana showed her recent second in the Irish 1,000 Guineas to have been no fluke as she survived being sandwiched leaving the starting stalls to complete a battling one-length success.

Soon recovering equilibrium after being left towards the back of the big field after the start, Seamie Heffernan steadily brought the winner through to take up the running two furlongs out and she kept on bravely to hold off the late challenges of Sentaril (5-1) and Aljamaaheer (4-1 favourite) who were arguably unsuited by the lack of early pace on their side of the pack.

O'Brien has a strong pack of three-year-old fillies this year, including Maybe and Homecoming Queen, both due to run later this week, but the trainer revealed that a bruised foot may force Maybe out of Friday's Coronation Stakes.

"She's a smart filly, she loves fast ground and shows plenty of speed," said the trainer of the winner.

"She got a great ride and it's been a top effort from everyone. You see a pecking order as it goes along on the track, we don't work them together at home. Maybe picked up a bruise after declaration time which has been treated but we'll need to see how she recovers. It usually takes a day to a day and a half and there isn't a lot of time."

Heffernan, riding his first Royal Ascot winner, received a seven-day suspension for his use of the whip and was also fined £500.

Sheikh Mohammed was delighted to be in the winner's enclosure after the Group Two Windsor Forest Stakes, but it was his wife Princess Haya who took the trophy as the winning owner after the John Gosden-trained Joviality scored at 11-1.

Chachaimaidee (4-1) arrived as if ready to throw down a winning challenge at the furlong-pole but her effort just petered out close home as Joviality strode on again to score by a neck, with Lay Time (9-1) third.

"We had to wait for her to come right in June but she's got a lot of tenacity and I really respect Henry's filly, who's very fast," said Gosden, who lost The Nile on an upsetting day for the stable on the first day of the meeting.

"But I thought if we can be in the right place and she has to come to us, we might outstay her. It was a thrilling performance. She wants a mile to a mile and a quarter so there are some nice races for her like the Nassau Stakes and the Prix de l'Opera - that is the elite end though and there are some rather nice fillies in France.

"We had a difficult day yesterday and it's a strange game - it's a game of vicissitudes."